DURHAM, N.C. -- Nearly a month after a massive coal ash spill at a Duke Energy plant contaminated the Dan River, state regulators in North Carolina announced late Friday that they have cited Duke for violations of environmental laws.

The North Carolina Department of Environment and Natural Resources has been accused by environmental groups for failing to take action against Duke Energy and cooperating too closely with the giant utility in dealing with the Feb. 2 spill.

In a news release issued at 6 p.m. Friday, the agency said it had issued notices of violation against Duke Energy earlier in the day for its handling of a 27-acre coal ash basin at a retired Duke coal-fired plant on the Dan River near North Carolina's border with Virginia.

The agency said Duke Energy could face fines of up to $25,000 per day for each violation, pending the outcome of a continuing investigation into the spill. The river bottom was coated with coal ash for 70 miles by the spill, the third-largest in U.S. history. Coal ash is residue left after treated coal is burned to produce electricity.

Jamie Kritzer, a spokesman for the Department of Environment and Natural Resources, said in a telephone interview Friday night that citations could not be issued until the agency had begun investigating the spill and assessed any damage. He said the state investigation is continuing, with more citations possible.

He said any fines would be imposed after the citation process is complete and the utility files a formal response. A brief statement issued by Duke Energy late Friday said: "We will respond to the state."

Duke Energy, the nation’s largest electricity utility, was cited for failing to control discharges of coal ash or contaminated coal ash water from the storage basin. The utility was also cited for violating surface water safety standards, failing to prevent pollutants from reaching the river and failing to obtain a state permit for discharges into the river.

The agency noted Duke Energy's "failure to take all reasonable steps to prevent any discharge ... with the reasonable likelihood of affecting human health or the environment."

"These are violations of state and federal law, and we are holding the utility responsible," John Skvarla, secretary of the Department of Environment and Natural Resources, said in the news release.

Skvarla, a Raleigh businessman, has been under fire from environmental groups since early last year, when he said his agency is a "partner" to those it regulates and considers them "customers." Skvarla was appointed by Republican Gov. Pat McCrory, who worked for Duke Energy for 28 years.

Federal prosecutors have said they launched a criminal investigation into the spill, issuing subpoenas to officials at the agency and Duke Energy to appear before a federal grand jury March 18.

Duke Energy initially said 52,000 to 82,000 tons of ash had spilled. It later reduced the estimate to between 30,000 and 39,000 tons.The spill released 27 million gallons of contaminated water.

The spill was caused by a ruptured storm-water pipe below the coal ash basin, according to Duke Energy. A second pipe at the site ruptured two weeks later, spilling an unknown amount of coal ash and contaminated water into the Dan. Duke Energy said it has sealed both pipes.

The state environmental agency acknowledged in August that Duke Energy was illegally discharging coal ash from the Dan River facility but did not fine the utility, according to the Southern Environmental Law Center, an advocacy group.

The state agency filed suit against Duke Energy in state court, alleging that coal ash was illegally seeping from coal ash basins at 14 North Carolina plants operated by the utility, including the Dan River facility. Environmental groups said the agency acted in order to block federal lawsuits against Duke Energy, announced earlier in the year by the environmental law center.

Those lawsuits, to be filed under the federal Clean Water Act, sought heavy fines and a requirement that Duke Energy move the coal ash basins to dry, lined landfills away from waterways.

The state agency reached an agreement with Duke Energy last year that would have imposed $99,000 in fines but would not have forced the utility to move or clean up coal ash basins. After the Feb. 2 spill, the agency asked a state judge to suspend the agreement.

On Tuesday, McCrory told Duke Energy that he wanted all of the utility’s coal ash containment basins moved away from drinking water sources. That same day, the state environmental agency said it was considering forcing Duke Energy to move coal ash at the Dan River site to a lined landfill away from waterways.

DURHAM, N.C. — North Carolina regulators who have been accused of lax oversight abruptly announced Tuesday that they may force Duke Energy to move its riverfront ash basin to a lined landfill away from waterways after one of its plants leaked tons of toxic coal ash into a major...

DURHAM, N.C. -- State regulators in North Carolina have ordered Duke Energy to contain a newly discovered leak of coal ash from a second storm-water pipe at a storage basin on the Dan River, where an earlier ruptured pipe released a massive coal ash spill on Feb. 2.

EDEN, N.C. – An environmental group Thursday challenged Duke Energy’s assurances that drinking water from the Dan River in North Carolina and Virginia remained safe despite a massive spill of toxic coal ash that released a deluge of murky gray sludge into the river Sunday.

Nurse Nina Pham — once the upbeat face of the Dallas hospital that confronted the country’s first Ebola case — sued the hospital’s parent company Monday, alleging that it had failed to protect her before and after she was diagnosed with the deadly disease last fall.

With no political solution in sight, Congress faces another deadline to fund the Homeland Security Department by midnight Friday – a do-over of last week's bitter battle as Republicans try to stop President Obama's immigration plans.